1. Technical Field
This invention generally relates to material handling systems, and more specifically relates to an overhead rail system.
2. Background Art
Overhead rail systems have become common in warehouse environments that require efficient movement of items that have considerable weight. Recently, overhead rail systems have been developed that can service multiple levels in a warehouse. As personnel began working around these rail systems that can service multiple levels, the risk from falling was recognized. As a result, safety rail systems were developed to provide a greater measure of safety to the warehouse worker. A safety rail system typically has rails that are placed perpendicular to the main overhead rail system so a person can move laterally with respect to the main overhead rail. A safety rail system typically includes rails of an I-beam or similar structure, and a trolley that rolls along the rails. The trolley typically includes an eyelet into which a hook may be attached. A worker wears a harness with a safety line that is terminated with a hook that may be attached to the eyelet on the trolley. Thus, when a worker reports to work, the worker puts on the harness, and clips the hook of the safety line coupled to the harness onto the trolley. The worker is then free to move in directions lateral to the main overhead rail to load and unload inventory to/from the main overhead rail. The safety line prevents the worker from falling to the ground if the worker slips and falls from an upper level in the warehouse, thereby preventing possible serious injury. Instead of striking the ground, the safety line will halt the descent of the falling worker, supporting the worker and avoiding contact with the lower level floor.
In the frozen food industry, overhead rail systems are often used to transport frozen food within a warehouse. Safety rail systems have been employed to avoid injury to workers in a frozen area. Sometimes a trolley needs to be added or removed from the safety rail system. For example, if an experienced employee is training a new employee, there may be a need for two safety trolleys on the safety rail system rather than just one. Known safety rail systems include end stops that are bolted onto the rail. Thus, if a new trolley needs to be added, bolts are loosened, then removed, the end stop is then removed, the new trolley can be placed on the rail, the end stop is then replaced, and the bolts are replaced and tightened into place. In some environments, performing these multiple operations may prove to be a nuisance that wastes time. In a frozen food environment, however, these detailed operations are much more difficult because they are either performed with gloved hands, which is difficult, or are performed using bare hands in freezing temperatures. Neither is a good solution. Without a rail system that allows trolleys to be placed onto the rail system and taken off the rail system without disassembling any portion of the safety rail system, the frozen food warehousing industry will continue to be plagued by inefficient mechanisms and methods for adding and removing trolleys from the safety rail system.
According to the present invention, a safety rail system includes a U-bracket for attaching a safety rail to an existing structural member, and an end stop that allows trolleys to be placed on a rail with one hand and removed with two hands, without any removal of bolts and without using any tools. The end stop is in a first position by the force of gravity that prevents a trolley from coming off the end of the rail. When a trolley is to be placed on the rail or removed from the rail, the end stop is pivoted upwards to allow wheels of the trolley to pass below the end stop. The end stop then returns to its normal, lower position, which prevents a trolley from accidentally coming off the end of the rail.
The foregoing and other features and advantages of the invention will be apparent from the following more particular description of preferred embodiments of the invention, as illustrated in the accompanying drawings.